20 Nov 2022 - 4 min read
Well, what a journey that’s been then … I started work on a clock for my relay computer back in May 2020 and today (20th Nov 2022) this post marks the end of it. …
01 Feb 2020 - 2 min read
As the clock struck midnight at the very end of 2019 I decided, over a glass of something sparkling, that I’d set myself a challenge to put out a series of six YouTube …
05 Jan 2020 - 1 min read
In my last post I covered off the full design for the decoder card so all that remains is to get it soldered up and tested. As before I’ve put a video together which …
21 Dec 2019 - 1 min read
In my last couple of posts I covered off the full design for the controller unit. As the PCBs have now arrived I can get on with soldering up the cards and giving them a test. …
20 Nov 2019 - 2 min read
In my last couple of posts I covered off the full design for the sequencer unit. With PCBs now safely arrived in the post I can get on with soldering up the cards and giving …
16 Jan 2018 - 3 min read
Fetch and Increment - Construction and Test
This is a bit of a landmark moment … at least for the construction of my relay computer. For a long time now my blog posts have been leading up to the point where my …
07 Jan 2018 - 1 min read
In my last two posts I covered the construction of the upper and lower incrementer cards. The lower card is a 16-bit half adder and the upper card is a 16-bit register. …
30 Nov 2017 - 2 min read
I’ve covered the construction of the upper and lower memory cards in my last two posts … it’s now time to bring those two cards together to form the memory …
11 Nov 2017 - 3 min read
In my last couple of posts I’ve been slightly distracted by some ‘miscellany’ but now I return to form and crack on with constructing the program counter. …
24 May 2016 - 2 min read
It’s finally time to give all the cards created so far a test so I can check everything works together as expected. This represents quite a bit of a milestone as the …
07 Jun 2015 - 3 min read
Decoder Construction: MOV-8, ALU & SETAB
In a change from prior form I’m combining the construction and testing of the next card in to a single post this time. Partly because this card is a nice easy one but …
16 May 2015 - 1 min read
Register Construction: Completed Instruction Register Full Test
Following on from my last post, and after popping in some relays, the instruction register is complete and looks like this: As usual I’ve put a video together that …
28 Jun 2014 - 2 min read
Register Construction: Completed A and D 8-bit Registers Full Test
The A/D Register card is now complete and looks like this: As usual I’ve put a video together that demonstrates this card in operation. This time I don’t show …
26 May 2014 - 2 min read
Register Construction: Completed B and C 8-bit Registers Full Test
The B/C Register card is now complete and looks like this: As usual I’ve put a video together which demonstrates this card in operation … firstly on its own but …
30 Mar 2014 - 3 min read
Following my last post on the completed backplane I’m now in a position to connect all the other completed cards together to test the full ALU. The ALU is made up of the …
26 Mar 2014 - 3 min read
ALU Construction: Completed Backplane
In my last post I mentioned I’d suffered a bit of a set back with the construction of the ALU backplane. Well, the short version of things is that I’ve admitted …
16 Mar 2014 - 2 min read
ALU Construction: Completed Control Card Full Test
The ALU Control Card is now complete and looks like this: This card was, on the whole, much simpler and quicker to put together than previous cards (despite me initially …
23 Feb 2014 - 1 min read
ALU Construction: Completed Arithmetic Card Full Test
The ALU arithmetic card is now complete! The final card looks like this: As I did for the ALU logic card before I’ve put the following YouTube video together which gives …
18 Dec 2013 - 2 min read
ALU Construction: Completed Logic Card Full Test
The ALU logic card is now finally complete! … well, it is now I’ve popped the last few relays into their sockets. The final card looks like this: As the old …